Commercial Rooftop HVAC Specialists

Rooftop HVAC and RTU Service Built Around Your Business

Advanced Service Company LLC provides rooftop HVAC installation, replacement, repair and maintenance for qualifying offices, restaurants, retail stores, shops and light-commercial buildings throughout North Alabama.

Request Commercial Service Call 256-432-7622

Roof access, crane requirements, curb compatibility and equipment availability affect project scheduling and pricing.

Commercial rooftop HVAC and RTU service in North Alabama
Since 2008Commercial Experience
HVAC #09005Alabama Certified
RTU ServiceRepair & Replacement
Commercial HVACQualifying Properties
Rooftop Equipment Options

Packaged Rooftop Systems for Commercial Comfort

We help compare RTU type, capacity, efficiency, stages, economizer, ventilation, controls and replacement requirements.

Packaged Rooftop Air Conditioners

Commercial packaged cooling systems that combine major components in one rooftop cabinet.

Rooftop Heat Pump Units

Packaged electric heating and cooling systems for qualifying commercial buildings.

Gas/Electric Rooftop Units

RTUs that provide electric cooling with natural-gas or propane heating.

Two-Stage Rooftop Units

Staged capacity can improve comfort, reduce cycling and better match changing building demand.

Variable-Speed & Inverter RTUs

Advanced compressor and blower technology can improve part-load efficiency and comfort.

Economizer-Equipped RTUs

Compatible economizers can use favorable outdoor air conditions to reduce mechanical cooling.

Make-Up Air & Ventilation RTUs

Selected systems can help meet outside-air and ventilation requirements for commercial spaces.

Replacement Rooftop Units

Modern equipment can replace aging rooftop systems while addressing curb, duct, controls and utility connections.

How RTUs Work

One Rooftop Cabinet Handles Heating, Cooling, Airflow and Ventilation

A rooftop unit combines major heating, cooling and airflow components in one cabinet. Supply and return ducts connect the unit to the building below.

Depending on configuration, the RTU may use gas heat, heat-pump heating, electric heat, staged cooling, an economizer and commercial control strategies.

Important: Roof curb, duct openings, drainage, electrical service, gas, airflow and controls must all be coordinated.

Major RTU Components

  • Compressor and coils
  • Supply and return fans
  • Heat exchanger or heat pump
  • Filters and drain system
  • Economizer and dampers
  • Control board and sensors
  • Roof curb and flashing
  • Thermostat or building controls
Commercial Advantages

Compact Rooftop Equipment with Flexible Commercial Controls

Space-Saving Design

Heating, cooling and airflow components are consolidated on the roof instead of using valuable indoor floor space.

Centralized Service Access

Roof-mounted equipment can simplify access for qualifying commercial service and replacement work.

Heating and Cooling in One Cabinet

Packaged rooftop units can provide complete year-round comfort from one system.

Commercial Capacity Options

A wide range of capacities and configurations can serve offices, retail, restaurants and light-industrial spaces.

Economizer Potential

Compatible systems may reduce compressor operation when outdoor conditions are suitable.

Zoning & Control Options

RTUs can integrate with programmable thermostats, zoning, building controls and occupancy schedules.

Replacement Flexibility

Curb adapters and field modifications may allow modern equipment to replace older rooftop units.

Indoor Air Quality Options

RTUs can support compatible filtration, ventilation and humidity-control accessories.

Reduce Downtime

Signs Your Rooftop Unit Needs Professional Attention

Poor Cooling or Heating

The RTU runs but cannot maintain the building temperature or recover after occupancy changes.

Frequent Cycling

Improper sizing, control issues, airflow restrictions or safety trips can cause repeated starts and stops.

High Energy Use

Dirty coils, worn components, economizer problems or aging equipment can increase operating cost.

Uneven Building Comfort

Duct leakage, zoning, airflow or control issues may create hot and cold areas.

Repeated Lockouts

Pressure, flame, airflow, sensor or control faults may cause recurring shutdowns.

Water Leaks

Drainage, curb, flashing, condensate or coil problems can allow water into the building.

Unusual Noise or Vibration

Fan, compressor, bearing, panel or mounting issues may require professional diagnosis.

Aging Major Components

An older compressor, heat exchanger, blower or control system may justify replacement planning.

RTU Repair

Diagnose Heating, Cooling, Airflow and Economizer Problems

We evaluate qualifying rooftop-unit concerns involving no cooling, no heat, lockouts, fan failures, electrical faults, refrigerant, ignition, controls, economizers and drainage.

View HVAC Repair Services
RTU Maintenance

Protect Reliability and Reduce Unexpected Downtime

Routine service can support filters, belts, coils, drains, airflow, controls, economizers, electrical components, refrigerant performance and heating safety.

View Maintenance Plans
Correct Sizing & Ventilation

Commercial RTU Selection Requires More Than Matching the Old Tonnage

Occupancy, lighting, equipment, ventilation, operating schedules, roof exposure, duct condition and building changes all affect load.

Load calculations and ventilation review help select the capacity and features the building actually needs.

Commercial Load Calculations

Review commercial heating and cooling load-calculation services.

View Load Calculations
Replacement Process

From Site Review to Rooftop Commissioning

1

Commercial Consultation

We discuss comfort problems, operating schedules, current equipment, building use and project goals.

2

Roof & Equipment Evaluation

We review access, curb condition, duct openings, electrical service, gas, drainage and existing controls.

3

Load & Capacity Review

Building load, occupancy and ventilation needs are evaluated instead of relying only on the old unit size.

4

System & Control Options

We compare RTU type, efficiency, stages, economizer, thermostat, zoning and ventilation features.

5

Written Proposal

You receive clearly explained equipment, crane needs, curb work, controls, included labor and exclusions.

6

Removal & Installation

The existing unit is removed and the replacement is set, connected and sealed using approved procedures.

7

Startup & Commissioning

We verify airflow, temperatures, refrigerant operation, gas heat, economizer, controls and safety functions.

8

Owner or Manager Walkthrough

We explain operation, filters, schedules, maintenance requirements and warranty information.

Essential RTU Replacement

Dependable packaged equipment for straightforward commercial replacements.

  • Matched capacity
  • Curb compatibility review
  • Professional installation
  • Startup and safety testing
Request Consultation
Popular

Enhanced Commercial Comfort

Staged operation, improved controls and economizer options for better performance.

  • Two-stage capacity
  • Programmable controls
  • Economizer options
  • Professional commissioning
Request Consultation

Premium RTU Controls

Advanced capacity, ventilation and control options for demanding commercial spaces.

  • Variable-speed options
  • Advanced economizer control
  • Zoning or BAS integration
  • Enhanced comfort features
Request Consultation
Project Planning

Commercial HVAC Financing for Approved Customers

Financing may help qualifying customers manage eligible rooftop HVAC replacement costs through monthly payments.

All financing is subject to credit approval, provider terms, rates, fees and program availability.

Explore Financing

Review available HVAC financing information for qualifying projects.

View Financing Options
Related Commercial Services

Complete Rooftop HVAC Support

Gas Packs

Compare packaged gas heat and electric cooling systems.

Learn more →

Heat Pumps

Review packaged and split heat-pump options.

Learn more →

Smart Thermostats

Control schedules, staging and compatible commercial equipment.

Learn more →

Load Calculations

Support proper RTU sizing and ventilation planning.

Learn more →

Indoor Air Quality

Coordinate filtration, ventilation and compatible IAQ options.

Learn more →

Duct Sealing

Reduce conditioned-air leakage from accessible commercial ductwork.

Learn more →

Rooftop HVAC Services Across North Alabama

Contact us to confirm rooftop HVAC installation, repair or maintenance availability for your commercial property.

Somerville, ALDecatur, ALHuntsville, ALMadison, ALAthens, ALHartselle, ALPriceville, ALTrinity, ALTanner, ALHarvest, ALHazel Green, ALEva, AL
Rooftop HVAC FAQ

RTU Installation, Repair, Economizer and Maintenance Questions

The visible questions below match the FAQPage schema included with this page.

A rooftop HVAC unit, or RTU, is a packaged heating and cooling system installed on the roof of a commercial building.

We service qualifying packaged air conditioners, heat pumps, gas/electric RTUs and related commercial rooftop equipment.

Many rooftop systems provide both heating and cooling in one cabinet.

RTUs are most common on commercial and light-industrial buildings, although some residential properties also use packaged rooftop equipment.

A gas pack is one type of packaged HVAC system. RTU is a broader term for rooftop packaged equipment, which may be gas/electric, heat pump or cooling-only.

Yes. We evaluate capacity, curb dimensions, duct openings, utilities, controls and roof access before recommending replacement options.

A curb adapter connects a new rooftop unit to an existing roof curb when the new unit footprint or duct openings differ.

Many rooftop replacements require a crane or lift, depending on equipment size, roof height and access.

Many straightforward replacements can be completed in one working day, while complex curb, duct, control or utility modifications may require more time.

Correct sizing supports comfort, efficiency, humidity control, ventilation and equipment life.

Yes. Commercial load calculations are available and may be recommended or required for rooftop replacement.

An economizer uses suitable outdoor air for cooling when outdoor conditions allow, reducing mechanical compressor operation.

A properly operating economizer may reduce cooling energy use when outdoor air conditions are favorable.

Sensors, dampers, actuators, controls and outdoor-air components can become dirty, stuck, misconfigured or electrically faulty.

Yes. Many RTUs can introduce controlled outside air through economizers or dedicated ventilation options.

Yes. Compatible zoning, multiple RTUs or building-control strategies can serve different areas and schedules.

Yes, when the thermostat or commercial control is compatible with the RTU stages and accessories.

Gas/electric RTUs may use natural gas or approved propane conversion components.

Backup heat requirements depend on the selected RTU, building load, outdoor conditions and control strategy.

Possible causes include refrigerant issues, dirty coils, failed fans, electrical faults, control problems or economizer issues.

Possible causes include ignition, gas, heat-pump, electric heat, thermostat, control or airflow problems.

Possible causes include roof-curb leaks, flashing problems, clogged condensate drains, cracked pans or coil icing.

Yes. We diagnose qualifying RTU heating, cooling, airflow, electrical, gas, control and economizer problems.

Commercial rooftop systems should receive regular maintenance based on usage, environment, filter loading and manufacturer recommendations.

Typical service may include filters, coils, belts, drains, electrical checks, controls, economizer operation, refrigerant performance and heating safety checks.

Yes. We replace qualifying belts and filters and inspect associated pulleys, blowers and airflow conditions.

The decision depends on age, repair cost, efficiency, downtime, warranty status and overall equipment condition.

Financing options may be available to approved customers for qualifying rooftop HVAC projects.

RTUs can be paired with compatible filtration and ventilation options, but they do not solve every indoor air concern by themselves.

We provide qualifying rooftop HVAC service for restaurants, retail, offices, shops and other light-commercial properties.

We serve Somerville, Decatur, Huntsville, Madison, Athens, Hartselle, Priceville and surrounding North Alabama communities.

Call or text 256-432-7622, or use the online booking link to request a rooftop HVAC consultation or estimate.

Request Commercial Rooftop HVAC Service

Schedule RTU repair, maintenance or a rooftop replacement consultation for your North Alabama business.

Request Commercial Service Call 256-432-7622

Regular hours: Monday–Friday, 7:00 AM–5:00 PM